Paleontology in Oregon facts for kids
Paleontology in Oregon refers to paleontological research occurring within or conducted by people from the U.S. state of Oregon. Oregon's geologic record extends back approximately 400 million years ago to the Devonian period, before which time the state's landmass was likely submerged under water. Sediment records show that Oregon remained mostly submerged until the Paleocene period. The state's earliest fossil record includes plants, corals, and conodonts. Oregon was covered by seaways and volcanic islands during the Mesozoic era. Fossils from this period include marine plants, invertebrates, ichthyosaurs, pterosaurs, and traces such as invertebrate burrows. During the Cenozoic, Oregon's climate gradually cooled and eventually yielded the environments now found in the state. The era's fossils include marine and terrestrial plants, invertebrates, fish, amphibians, turtles, birds, mammals, and traces such as eggs and animal tracks.
Oregon has a long tradition of paleontological research. Local Native Americans devised myths to explain fossils. By the mid-19th century local fossils had come to the attention of formally trained scientists, and modern research has produced data on climate change and extinction.
The Oligocene dawn redwood Metasequoia occidentalis is the Oregon state fossil.
Prehisto Precambrian There are no known rocks in Oregon from Precambrian times. Geologists infer that the area now occupied by Oregon must have been submerged deep on the ocean floor during that period.
Contents
Prehistory
No Precambrian fossils are known from Oregon, so the state's fossil record does not begin until the Paleozoic. No rocks are known in Oregon from the Cambrian to the Silurian, although the state was probably submerged by the sea. From the Devonian to the Permian a chain of volcanic islands began forming in the state. These islands were home to lagoons and surrounded by coral reefs. Brachiopods also inhabited the nearby waters. Plant fossils suggest a rich terrestrial flora was not far away. Oregon remained mostly covered in seawater throughout the Mesozoic. Local marine invertebrate life included corals, oysters, and snails. Local vertebrates included ichthyosaurs and pterosaurs. Although it has been claimed that no dinosaurs are known to have inhabited Oregon, fossils of a possible hadrosaurid ("duck-billed" dinosaur) were discovered in the southwestern corner of the state, believed to be Campanian in age. During the Cretaceous period, between 90 and 100 million years ago, most of Oregon was covered by the ocean. Plesiosaurs swam and fed on the fish of this Oregonian ocean.
Oregon remained partially covered by the sea into the Cenozoic. Contemporary marine life included fig and turret-shelled snails. During the Tertiary, Oregon trees like Alniphyllum, ash, beech, cinnamon, Gargura, hemlock, hickory, hornbeam, oak, persimmon, pine, redwood, and sycamore grew in Oregon. Alders were also present. The most common local trees were the redwoods and sycamores. The Tertiary petrified wood of Oregon is sometimes partially opalized. Oregon's sea levels fluctuated rapidly during the Eocene to Oligocene interval. Mollusks were diverse in Oregon during the Eocene, with at least 25 species known from the Fern Ridge Dam area. From the Eocene to the Oligocene, the Sunset Highway area was covered in seawater. During this interval it was inhabited by invertebrates like crinoids, crustaceans, echinoderms, gastropods, and scaphopods. Local Eocene sharks left their teeth behind in the Rocky Point Quarry to the west of the Nehalem River. Crocodiles lived in Oregon from 60 to 45 million years ago. The local flora from this interval also left behind remains that would later fossilize. As the Cenozoic proceeded, the climate of Oregon became cooler and drier. Local marine life took on a more modern aspect. These were inhabited by creatures like bear dogs, camels, cats, deer, gomphotheres, and horses. Local mountain building added the Cascade and Coast ranges to the local topography. Oligocene crinoids were preserved near Vernonia. During the early Oligocene, Oregon's terrestrial environments were home to Cinnamomum, cycads, palms, the primitive sycamore Platanophyllum angustilobus, and walnuts. The plant fossil sites to the east of Clarno's Ferry are one of the few places in the world where the fruits, leaves, and wood, of prehistoric plants were preserved in a single location. Late Oligocene fossil salamanders were preserved near north Goshen. During the Oligocene and Miocene, volcanic eruption-emitted clouds of ash buried many animals. During the Pleistocene, mountains developed icy caps. A variety of environments filled the flatter areas of the state. Among these were arid plains, forests, and savannahs. Volcanic eruptions occurred sporadically in the Cascade Mountains throughout the rest of the Cenozoic. During the Pleistocene, relatives of modern elephants left behind teeth and fragmentary skeletal remains in the Spencer Creek area and other parts of the Willamette Valley.
History
Scientific research
Paleontology in Oregon has a long history. In 1861, a company of soldiers that arrived in Fort Dalles after visiting the Crooked River region brought back fossil bones and teeth, among which was a well-preserved rhinoceros jaw. The find brought instant fame to the John Day region of Oregon as a source of fossils. The pastor of the fort's Congregational church, Thomas Condon, happened to be an enthusiast of geology and paleontology. In 1862, some soldiers were dispatched with supplies to Harney Valley. Condon went along with them and prospected for fossils when the troops passed back through the Crooked River area. He went fossil collecting again in 1863 and discovered rich fossil deposits north of Picture Gorge in the John Day River valley. He realized that he had stumbled on a find of major scientific importance. Since he himself had no scientific qualifications or references to use in identifying fossils, Condon sent some fossils to O. C. Marsh of Yale University. Marsh replied with a request for Condon to guide an expedition to the area in which he found the fossils. Condon obliged and over the ensuing years a series of fossil hunting expeditions ventured into the John Day fossil beds. Fossils uncovered during these excavations ended up in a wide variety of prestigious museums like the American Museum of Natural History and Smithsonian Institution. In 1962, two University of Oregon students discovered 35 bones fragments and fifteen teeth. These remains were left by an ancient crocodile that lived 60 to 45 million years ago. The specimen was the only known fossil crocodile found west of the Rocky Mountains and has been considered one of the most significant fossil finds of the mid-to-late twentieth century in Oregon. In 1980, Pleistocene bear fossil footprints were reported from Lake County. The 9-meter trackway consists of footprints up to 40 cm long. This suggests a body size similar to the largest modern bears. These are among the few known Pleistocene fossil footprints in the western United States. These prints were likely left by Arctotherium, the only known mammal of the age who could account for them.
More recently, during the summer of 2004, amateur paleontologists Mike Kelly and Greg Kovalchuk were looking for invertebrate fossils on public land in the grey hills of the central region of the state. Kelly examined a rock that turned out to preserve a tooth. The fossil hunters examined the area around the fossil and found several more teeth downslope from the original. Although they knew the find was important they both knew collecting vertebrate fossils on public land was a crime. So, they took down the fossil's GPS coordinates. They alerted the Paleontology Program Coordinator of the Bureau of Land Management for Washington and Oregon, John Zancanella. Kelly and Kovalchuk agreed to meet Zancanella at the site to verify the fossil's location. After relocating the remains, the Bureau of Land Management arranged for the Curator of the Vertebrate Paleontology of the Museum of Geology at the South Dakota School of Mines, Dr. James E. Martin, to excavate the fossils. Martin is a prominent marine reptile researcher. Kelly and Kovalchuk had discovered the lower jaw of a plesiosaur, roughly three feet long. The discovery was only the third vertebrate fossil from the late Mesozoic era in the entire Pacific Northwest. It was also the region's first plesiosaur. The fossil was set to be curated by South Dakota's Museum of Geology, with a replica intended to be displayed locally to help educate the public about the region's fossils. Zancanella described Kelly and Kovalchuk's conduct throughout their discovery as "exemplary" and concluded that they "did everything right". In 2005, the Eocene dawn redwood Metasequoia occidentalis was designated the Oregon state fossil.
Protected areas
Natural history museums
- University of Oregon Museum of Natural and Cultural History, Eugene
Notable locations
Fossil localities
- Astoria Formation
- Blue Mountains
- Coyote Butte Formation
- Curry County
- Fossil Lake
- Keasey Formation
- Nye Formation
- Pittsburg Bluff Formation
- Wallowa Mountains
Protected areas
Natural history museums
Images for kids
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A trilobite in the genus Cummingella, related to C. oregonensis
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Artist's reconstruction of ichthyosaurs in the genus Shastasaurus
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A trace fossil attributed to the genus Skolithos
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Horns and other fossils attributed to Dromomeryx
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Artist's reconstruction of the saber-toothed salmon Oncorhynchus rastrosus
